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wildlifewarrior
01-28-2015, 07:31 AM
Good Morning,

I was curious to know if a sap ladder using star fittings needs to be directly aligned below the upper tubing. I understand that the gases are what lift the sap, so I assume that they need to be oriented one directly over the other for efficiency. I would think that if they are not directly over one another that the sap would slide down the lower side while the air moves past it on the upper side.

Thanks
Mike

BreezyHill
01-28-2015, 07:58 AM
Great question!

Depends on the size of the riser in diameter. if using 1" then yes as straight as possible or you will get more slippage.

On 5/16 no. I have several that go from one side of the tree around the south face for solar thawing, to the opposite side of the tree.10484

This is an 18' ladder, #3 in a series of 7. This one has about 300 taps going through it now. It also has a dry line that was added last season after this pic that is a 1" riser. Not much sap makes it up the 1" riser due to the amount of slippage. The 1" riser is a straight up after the connection point.

Sap will travel up the risers on its own...I inject air to speed the process so that the main feeding the ladder does not flood and stop vacuum transfer. I can also increase the lines carry capacity due to the speed of sap thru the risers this way. This is my tallest ladder. Most others are between 12 and 16 feet. I am not a fan of heights and the son in the pic is off to college until the season of 2018.

wildlifewarrior
01-28-2015, 10:09 AM
Our lift is about 8 feet, the initial line was in place last year and we are adding in the second one, the way the topography works out, the two lines are about 4 feet apart, left to right. it is a 1'' main, I was worried about pooling and decreased vac as well. The whole line system is about 700 feet, with the lift being in the last 150-200 feet or so.
Thanks
Mike

BreezyHill
01-28-2015, 11:04 AM
Not a problem as long as you have enough vac to the point of the ladder.
For an 8' rise you may need to inject a tiny amount of air but likely not. The deciding factor is if at peak flow you have pooling in the bottom of the main then you need to inject a tiny amount of air to clear the pool. If not you will have limited vac transfer. Fast moving ladders have very good vac transfer slow movers have poor transferal.

When I say tiny it is less than what a 28 ga hypo needle will allow into the system. With all of my injectors together from last year I had less than 0.2 cfm of injection for a total of 8 ladders. Far less than what our old mechanical releaser used.

The 4' when using stars will not be an issue, I beat that #3 has closer to 6' of offset from the ladders due to the tree size, the space needed for the three stars to be set on the main and space from the tree for better thawing of the lines. To close to the tree and the bottom wont thaw if the temp rises after 1 2 pm.

4' for larger pipe would be a killer on 3/4 or 1". I will be testing a 1/2" riser this season to see if I can get them to work efficiently.

Keep the ladders in the sun as much as possible for a quicker thaw time. Tops also as slush is hard to thaw when it is packed from the vacuum pulling it into the fittings.